Reelin is a serine protease of the extracellular matrix
Reelin is a serine protease of the extracellular matrix
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DOI：
10.1074/jbc.m106996200
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发表时间：
2002-01-04
影响因子：
4.8
通讯作者：
Keller, F
中科院分区：
文献类型：
--
作者：
Quattrocchi, CC;Wannenes, F;Keller, F
Reelin是一种细胞外基质蛋白，在中枢神经系统的发育中起着关键作用。Reelin在成人大脑中也有表达，特别是在大脑皮层，在那里它可能在突触可塑性中发挥作用。Reelin在分子水平上的作用机制一直是几种假说的主题。在这里，我们证明了Reelin是一种丝氨酸蛋白酶，其蛋白分解活性与其功能有关，因为(I)Reelin在HEK 293T细胞中的表达削弱了它们在纤维连接蛋白涂层表面的黏附能力，并且通过微摩尔浓度的丝氨酸水解酶抑制剂二异丙基氟磷酸盐恢复与纤维连接蛋白的黏附；(Ii)纯化的Reelin与位于丝氨酸水解酶活性催化部位的丝氨酸残基不可逆结合的陷阱探针FP-Peg-bitin结合；(Iii)纯化的Reelin迅速降解纤维连接蛋白和层粘连蛋白，而IV型胶原的降解速度要慢得多；纤维连接蛋白的降解被丝氨酸蛋白酶的抑制剂和单抗CR-50所抑制，CR-50是一种已知在体外和体内都能阻断Reelin功能的抗体。Reelin对细胞外基质黏附分子和/或神经元上受体的蛋白分解活性可能解释了Reelin调节神经元迁移和突触可塑性的机制。
Reelin is an extracellular matrix protein that plays a pivotal role in development of the central nervous system. Reelin is also expressed in the adult brain, notably in the cerebral cortex, where it might play a role in synaptic plasticity. The mechanism of action of reelin at the molecular level has been the subject of several hypotheses. Here we show that reelin is a serine protease and that proteolytic activity is relevant to its function, since (i) Reelin expression in HEK 293T cells impairs their ability to adhere to fibronectin-coated surfaces, and adhesion to fibronectin is restored by micromolar concentrations of diisopropyl phosphorofluoridate, a serine hydrolase inhibitor; (ii) purified Reelin binds FP-Peg-biotin, a trap probe which irreversibly binds to serine residues located in active catalytic sites of serine hydrolases; (iii) purified Reelin rapidly degrades fibronectin and laminin, while collagen IV is degraded at a much slower rate; fibronectin degradation is inhibited by inhibitors of serine proteases, and by monoclonal antibody CR-50, an antibody known to block the function of Reelin both in vitro and in vivo. The proteolytic activity of Reelin on adhesion molecules of the extracellular matrix and/or receptors on neurons may explain how Reelin regulates neuronal migration and synaptic plasticity.